Graham Number Calculator
Calculate any stock's intrinsic value using Benjamin Graham's proven formula. Find out if a stock is undervalued, fairly priced, or overpriced — instantly.
Calculate Graham Number
Earnings per share for the last 12 months
Company's book value divided by shares outstanding
Current market price per share
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Graham Number Quick Reference
What Is the Graham Number?
The Graham Number is a formula created by legendary value investor Benjamin Graham to estimate the maximum fair price for a stock based on its earnings and book value. It's one of the simplest ways to screen for undervalued stocks.
Graham Number = √(22.5 × EPS × Book Value Per Share)
How to Use the Graham Number
- If the Graham Number is higher than the stock price — The stock may be undervalued. The bigger the gap, the larger your margin of safety.
- If the Graham Number equals the stock price — The stock is roughly fairly valued according to Graham's criteria.
- If the Graham Number is lower than the stock price — The stock may be overvalued. Proceed with caution.
What Is Margin of Safety?
Margin of safety is the difference between a stock's intrinsic value (Graham Number) and its current market price, expressed as a percentage. Graham recommended buying stocks only when they trade significantly below their intrinsic value — typically with a margin of safety of 30% or more.
Where Does 22.5 Come From?
Graham believed a stock should have a P/E ratio no higher than 15 and a price-to-book ratio no higher than 1.5. Multiplying 15 × 1.5 gives 22.5. This constant represents his maximum acceptable valuation benchmark.
Limitations of the Graham Number
The Graham Number doesn't account for growth rates, competitive moats, debt levels, or industry dynamics. It works best for stable, established companies with consistent earnings. Use it alongside other metrics like P/E ratio, free cash flow yield, and debt-to-equity for a complete picture.
Want to go deeper? Read our complete guide to value investing →